/*
 *  fx/Twister.h
 *
 *  Copyright 2009 Peter Barth
 *
 *  This file is part of Milkytracker.
 *
 *  Milkytracker is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  Milkytracker is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with Milkytracker.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef TWISTER__H
#define TWISTER__H

#include "FXInterface.h"
#include "Math3d.h"

#define NUMPOINTS 4

class Twister : public FXInterface
{
    private:
        int center;

        unsigned short* texture;
        int* zbuffer;

        struct MyVertex
        {
            VectorFP p;
            int u;
        };

        MyVertex sourcePoints[NUMPOINTS + 1];
        MyVertex newPoints[NUMPOINTS + 1];

        int sinTable[1024];
        int cosTable[1024];

        int mySin(int phi)
        {
            int t = (phi & 255);

            int s1 = sinTable[(phi >> 8) & 1023];
            int s2 = sinTable[((phi >> 8) + 1) & 1023];

            return (s1 * (255 - t) + t * s2) >> 8;
        }

        int myCos(int phi)
        {
            int t = (phi & 255);

            int s1 = cosTable[(phi >> 8) & 1023];
            int s2 = cosTable[((phi >> 8) + 1) & 1023];

            return (s1 * (255 - t) + t * s2) >> 8;
        }
    public:
        Twister (int width, int height, int center = -1);
        ~Twister ();

        void render(unsigned short* vscreen, unsigned int pitch);
        void update(float syncFrac);

};

#endif